Administration Of L-asparaginase Research Articles

Predictive factors for L-asparaginase hypersensitivity in pediatric acute lymphoblastic leukemia.

L-Asparaginase is a crucial component of acute lymphoblastic leukemia (ALL) treatment. However, hypersensitivity is a common adverse event. This study aimed to identify risk factors for L-asparaginase hypersensitivity in childhood ALL. Children treated for ALL at Chiang Mai University Hospital, Thailand, between 2005 and 2020 were included. Demographic data, clinical characteristics, and factors related to L-asparaginase were retrospectively reviewed. L-Asparaginase hypersensitivity was observed in 24 of 216 children with ALL (11.1%). All patients received native L-asparaginase intramuscularly, and events occurred exclusively during the post-induction phase without concurrent corticosteroid use. Univariable analysis showed that relapsed ALL, higher accumulated doses, increased exposure days, and longer interval between drug administrations were potential risk factors. In multivariable logistic regression analysis, interruption of L-asparaginase administration for ≥ 52weeks and exposure duration of ≥ 15days were independent risk factors, with adjusted odds ratio of 16.481 (95% CI 3.248-83.617, p = 0.001) and 4.919 (95% CI 1.138-21.263, p = 0.033), respectively. Children with ALL who require re-exposure to L-asparaginase after 52-week interruption or who have received L-asparaginase for ≥ 15 exposure days are at risk of developing L-asparaginase hypersensitivity. Further management strategies in this setting should be evaluated.

Efficacy and adverse events of L-Asparaginase administration as a first-line treatment for feline large-cell gastrointestinal lymphoma.

L-Asparaginase (L-Asp) is often used to induce remission in feline large-cell gastrointestinal lymphoma (LCGIL). However, no study has evaluated the efficacy and adverse events following the initial use of this drug as a first-line treatment in feline LCGIL. We retrospectively reviewed medical records of cats with LCGIL treated with L-Asp to induce remission. This study included 43 cats. The response rate (RR) after the first administration of L-Asp was 37.2% (Complete remission: 7.0%, partial remission: 30.2%). RR was significantly higher in cases with primary gastric lesions (64.3%) than in those with primary intestinal lesions (24.1%) (P=0.018), and it was also higher in cases without anemia (57.1%) than those with anemia (15.0%) (P=0.009). The most common adverse event was hyperammonemia, which occurred in 10 of 12 cases where we could compare plasma ammonia concentrations before and after the first dose of L-Asp. Plasma phosphate concentrations were also significantly increased (P<0.001) within 24 hr after the first dose. Decreased appetite, vomiting, and diarrhea were also observed in five, three, and seven cases, respectively, and Grade 3 or higher gastrointestinal signs were observed as adverse events in three cases. The median overall survival of all cats was 150 days (range, 5-1,065 days), and the median progression-free survival was 104 days (range, 2-978 days). In conclusion, L-Asp was effective to induce remission, and severe adverse events were uncommon in feline LCGIL.

Thromboprophylaxis with Intermediate Dose Low Molecular Weight Heparin in Adults Undergoing Induction with L-Asparaginase for Acute Lymphoblastic Leukemia

Introduction Adolescents and young adults (AYA, defined as age 15-39 years) with acute lymphoblastic leukemia (ALL) have a poorer prognosis than their pediatric counterparts. To replicate the success of ALL treatment in children, pediatric-inspired regimens have been incorporated into the treatment of AYA and often include the use of L-asparaginase. Rates of thrombosis in adults receiving L-asparaginase for treatment of ALL have been reported to be as high as 34%, compared to only about 5% in pediatric patients. The risk of thrombosis is elevated primarily during the induction phase of treatment. Several strategies have been studied in adults, including antithrombin III replacement, fresh frozen plasma replacement, and prophylactic dosing of anticoagulation, however no clear guidelines exist on how to prevent thrombosis in these high-risk patients. To prevent L-asparaginase-induced thrombotic events, our institution implemented a standard practice of 1mg/kg/day of low molecular weight heparin (LMWH), a dose in-between prophylactic and therapeutic dosing, administered to all adults with ALL who were treated with L-asparaginase during induction chemotherapy. In this current study, we report data from patients who have been treated with this strategy from 2012 to present, focusing on the antithrombotic efficacy and safety of 1mg/kg/day LMWH in this population. Methods This retrospective chart review included 62 patients who received prophylactic anticoagulation with the LMWH enoxaparin (1mg/kg/day) while undergoing induction chemotherapy with L-asparaginase for ALL at the Oregon Health &amp; Science University from 2012 to present. Anticoagulation with enoxaparin was initiated with the first dose of L-asparaginase and continued until the day of discharge or day 30 of induction. The primary outcome was the incidence of thrombosis within the first 30 days of L-asparaginase administration. Minor and major bleeding events, as defined by the International Society of Thrombosis and Haemostasis (ISTH), were recorded. Statistical analysis with univariate regression models was performed to evaluate the association of thrombotic events with demographic, disease and treatment variables. Results Sixty-two patients received 1mg/kg/day LMWH prophylaxis during ALL induction between January 2012 and June 2023 (43 with B-ALL and 19 with T-ALL). Median age at induction was 25.7 years (range 18-39 years). A majority of patients (83.9%) received the maximum dose of 2500mg/m 2 of L-asparaginase. Four patients (6.5%; 95% CI 1.8%-15.7%) experienced a thrombotic event within the first 30 days of induction with L-asparaginase; 3 of the events were catheter-associated and were treated supportively or with catheter removal, and 1 patient developed a distal lower extremity deep vein thrombosis related to myositis. Median time to thrombosis was 13.5 days (range 11-22 days). There were no significant associations between development of thrombotic events with age, gender, B- or T-cell precursor, or dose of L-asparaginase. No thrombosis-related deaths or major bleeding events occurred. Conclusions Prophylactic anticoagulation with intermediate dose 1mg/kg/day LMWH in adults with ALL undergoing induction chemotherapy with L-asparaginase is a safe and an effective strategy to prevent serious thrombotic events. Our institutional rate of 6.5% of patients experiencing thrombotic events during induction with L-asparaginase, with all of the events being clinically low risk, compares favorably to historically reported rates in adults and approaches the low rates reported in children. Further prospective research is warranted.

Asparaginase-Induced Acute Necrotizing Pancreatitis Resulting in Chronic Pancreatitis and Pseudocyst in an Adult with Acute Lymphocytic Leukemia

L-Asparaginase is one of the main chemotherapy regiments for acute lymphocytic leukemia (ALL) management. Acute pancreatitis is one of the serious side effects of l-asparaginase administration and may lead to interruption of chemotherapy cycle. Long term complications may be devastating for patients which include of pseudocyst pancreas and chronic pancreatitis. Asparaginase induced pancreatitis is rare among adult due to the nature of ALL which commonly occurred in children population. The pathophysiology of asparaginase induced pancreatitis is still unclear. Here we present 18-year-old male with ALL and asparaginase induced acute necrotizing pancreatitis which complicated to chronic pancreatitis and pseudocyst.

Therapeutic impact of purified Trichoderma virideL-asparaginase in murine model of liver cancer and in vitro Hep-G2 cell line

BackgroundHepatocellular carcinoma (HCC) is among the common cancers, but difficult to diagnose and treat. l-asparaginase has been introduced in the treatment protocol of pediatric acute lymphoblastic leukemia (ALL) since the 1960s with a good outcome and increased survival rates to nearly 90%. Moreover, it has been found to have therapeutic potential in solid tumors. Production of glutaminase-free-l-asparaginase is of interest to avoid glutaminase-related toxicity and hypersensitivity. In the current study, an extracellular l-asparaginase that is free of l-glutaminase was purified from the culture filtrate of an endophytic fungus Trichoderma viride. The cytotoxic effect of the purified enzyme was evaluated in vitro against a panel of human tumor cell lines and in vivo against male Wister albino mice intraperitoneally injected with diethyl nitrosamine (200 mg/kg bw), followed by (after 2 weeks) oral administration of carbon tetrachloride (2 mL/kg bw). This dose was repeated for 2 months, and after that, the blood samples were collected to estimate hepatic and renal injury markers, lipid profiles, and oxidative stress parameters. Resultsl-asparaginase was purified from T. viride culture filtrate with 36 purification folds, 688.1 U/mg specific activity, and 38.9% yield. The highest antiproliferative activity of the purified enzyme was observed against the hepatocellular carcinoma (Hep-G2) cell line, with an IC50 of 21.2 g/mL, which was higher than that observed for MCF-7 (IC50 34.2 g/mL). Comparing the DENA-intoxicated group to the negative control group, it can be demonstrated that l-asparaginase adjusted the levels of the liver function enzymes and the hepatic injury markers that had previously changed with DENA intoxication. DENA causes kidney dysfunction and altered serum albumin and creatinine levels as well. Administration of l-asparaginase was found to improve the levels of the tested biomarkers including kidney and liver function tests. l-asparaginase treatment of the DENA-intoxicated group resulted in a significant improvement in the liver and kidney tissues to near normal similar to the healthy control group. ConclusionThe results suggest that this purified T. viridel-asparaginase may be able to delay the development of liver cancer and may be used as a potential candidate for future application in medicine as an anticancer medication.

Risk Stratified Therapy with Nelarabine and Intensified Administration of L-Asparaginase for Newly Diagnosed T-Cell Acute Lymphoblastic Leukemia in Adolescents and Young Adults (JPLSG T-11/JALSG T-ALL-211-U): An Intergroup Phase 2 Study

Risk Stratified Therapy with Nelarabine and Intensified Administration of L-Asparaginase for Newly Diagnosed T-Cell Acute Lymphoblastic Leukemia in Adolescents and Young Adults (JPLSG T-11/JALSG T-ALL-211-U): An Intergroup Phase 2 Study

L-asparaginase: New about Well-Known Drug

The history of asparaginase clinical use is inextricably linked to the improvement of treatment programs for acute lymphoblastic leukaemia (ALL). Asparaginase, obtained from E. coli, has become the crucial part in the protocols for the treatment of ALL in children and adults since the 1960s-1970s due to its antitumor effect on lymphoid leukemia cells. Despite the evolution of therapeutic approaches in ALL management, changes in used chemotherapeutic agents, their administration regimens and doses, the asparaginase remains one of the leading therapeutic agents in ALL patients. With time ideas about the asparaginase mechanisms have expanded, new data have been accumulated on adverse effects (allergic reactions, thrombotic complications, pancreatitis, hepatic dysfunction, etc.). The asparaginase obtained from Erwinia chrysanthemi and PEGylated forms of the drug were used to reduce the frequency of any of such adverse effects. This literature review provides current concepts on the mechanism of L-asparaginase dosage forms action, describes side effects associated with the use of this medication. We also present our own clinical case of L-asparaginase (obtained from Erwinia chrysanthemi) administration in ALL patient with allergic reaction to PEG-L-asparaginase.

Efficacy and adverse events of continuous l-asparaginase administration for canine large cell lymphoma of presumed gastrointestinal origin.

We examined the efficacy and adverse events of continuous l-asparaginase administration in dogs with large cell lymphoma of presumedgastrointestinal (GI) origin. We retrospectively reviewed medical records of dogs with large cell lymphoma of presumed GI origin treated with continuous l-asparaginase administration from 2009 to 2018. We collected information on the signalment, lesion site, complete blood count, serum biochemical profile, diagnostic imaging findings, cytological and histopathological findings, immunophenotype, l-asparaginase administration frequency, treatment response, adverse events, rescue protocol, and patient outcomes. Clinical outcomes were assessed using medical records or by contacting the owner or referring veterinarian. Thirty-two dogs with large cell lymphoma of presumed GI origin received weekly l-asparaginase administration. The median number of l-asparaginase injections was seven (range: 1-30). Although two of the 32 dogs had GI toxicity of grade 3 or higher, none developed a hypersensitivity reaction. The response rate based on ultrasonographic findings was 18/32 (56%) and that based on clinical signs was 30/32 (94%). The median overall progression-free survival was 50 days (range: 2-214 days), and median overall survival was 147 days (range: 2-482 days). Adverse events associated with continuous l-asparaginase administration were rare. Clinical signs at diagnosis improved in most cases. Based on these results, continuous l-asparaginase administration appears to be a reasonable treatment option for dogs with large cell lymphoma of presumed GI origin.

Acquired hypofibrinogenemia in patients with leukemia during steroid therapy

Acquired hypofibrinogenemia is observed in patients with severe liver disease, disseminated intravascular coagulation, and high-volume perioperative fluid replacement. In lymphoblastic leukemia, hypofibrinogenemia is most frequently caused by the administration of L-asparaginase. Here we report the cases of two patients with acquired hypofibrinogenemia that occurred during steroid-containing chemotherapy treatment against lymphoblastic blast crisis of chronic myeloid leukemia in the first case and acute lymphoblastic leukemia in the second case. Administration of steroids repeatedly and promptly caused hypofibrinogenemia, irrespective of the products (prednisolone, dexamethasone, or methylprednisolone) or routes (oral or intravenous) that were used. Monitoring of the fibrinogen levels, especially during the first course of steroid therapy, would be useful for early diagnosis.

Improved outcome in childhood acute lymphoblastic leukemia despite reduced use of anthracyclines and cranial radiotherapy: results of trial ALL-BFM 90

AbstractTrial ALL-BFM 90 was designed to improve outcome in patients with childhood acute lymphoblastic leukemia (ALL) by using a reduced treatment regimen. Patients were stratified into a standard-risk group (SRG), a medium-risk group (MRG), both defined by adequate early treatment response; and a high-risk group (HRG), defined by inadequate response to the cytoreductive prednisone prephase, induction failure, or Philadelphia-chromosome–positive ALL. Four treatment modifications were evaluated: dose intensification in induction by a more rapid drug sequence; administration of l-asparaginase during consolidation therapy in the MRG (randomized); enforced consolidation by rotational elements in the HRG; and reduction in the dose of anthracyclines and use of only 12-Gy preventive cranial radiotherapy in the MRG and HRG, with the aim of avoiding toxicity. Among all 2178 patients (≤ 18 years of age), the 6-year event-free survival (EFS) rate (± SE) was 78% ± 1%, with a median observation time of 4.8 years. EFS was 85% ± 2% in the SRG (n = 636) and 82% ± 1% in the MRG (n = 1299). l-asparaginase did not improve outcome in the MRG: the event-free interval was 83% ± 2% withl-asparaginase (n = 528) and 81% ± 2% without it (n = 557). Because there were more systemic relapses in the HRG (n = 243), EFS was 34% ± 3%, an outcome inferior to that in the HRG in a previous trial, ALL-BFM 86, in which EFS was 47% ± 5% (P = .04). The rates of isolated central nervous system relapse in the MRG and HRG were 0.8% and 1.6%, respectively; thus, the 12-Gy preventive cranial radiotherapy regimen apparently provided sufficient central nervous system prophylaxis. The overall improvement over the results in ALL-BFM 86 (6-year EFS, 72%; P = .001) was based on fewer recurrences among patients in the MRG with B-cell-precursor ALL, indicating an advantage of more condensed induction therapy. In multivariate analysis, inadequate in vivo response emerged as the strongest adverse prognostic variable.

Metabolic profile of leukemia cells influences treatment efficacy of L-asparaginase

BackgroundEffectiveness of L-asparaginase administration in acute lymphoblastic leukemia treatment is mirrored in the overall outcome of patients. Generally, leukemia patients differ in their sensitivity to L-asparaginase; however, the mechanism underlying their inter-individual differences is still not fully understood. We have previously shown that L-asparaginase rewires the biosynthetic and bioenergetic pathways of leukemia cells to activate both anti-leukemic and pro-survival processes. Herein, we investigated the relationship between the metabolic profile of leukemia cells and their sensitivity to currently used cytostatic drugs.MethodsAltogether, 19 leukemia cell lines, primary leukemia cells from 26 patients and 2 healthy controls were used. Glycolytic function and mitochondrial respiration were measured using Seahorse Bioanalyzer. Sensitivity to cytostatics was measured using MTS assay and/or absolute count and flow cytometry. Mitochondrial membrane potential was determined as TMRE fluorescence.ResultsUsing cell lines and primary patient samples we characterized the basal metabolic state of cells derived from different leukemia subtypes and assessed their sensitivity to cytostatic drugs. We found that leukemia cells cluster into distinct groups according to their metabolic profile. Lymphoid leukemia cell lines and patients sensitive to L-asparaginase clustered into the low glycolytic cluster. While lymphoid leukemia cells with lower sensitivity to L-asparaginase together with resistant normal mononuclear blood cells gathered into the high glycolytic cluster. Furthermore, we observed a correlation of specific metabolic parameters with the sensitivity to L-asparaginase. Greater ATP-linked respiration and lower basal mitochondrial membrane potential in cells significantly correlated with higher sensitivity to L-asparaginase. No such correlation was found in the other cytostatic drugs tested by us.ConclusionsThese data support that cell metabolism plays a prominent role in the treatment effect of L-asparaginase. Based on these findings, leukemia patients with lower sensitivity to L-asparaginase with no specific genetic characterization could be identified by their metabolic profile.

Effect of Dose and Schedule of L-Asparaginase Administration on Early Minimal Residual Disease in Acute Lymphoblastic Leukemia

AbstractBackground and Objectives: L-asparaginase has become the backbone of acute lymphoblastic leukemia induction. In Berlin–Frankfurt–Munster (BFM) 95/2000 protocols, L-asparaginase was given twice weekly for initial 4 weeks. While sufficient L-asparaginase levels are important, there is no apparent correlation between high L-asparaginase levels and minimal residual disease (MRD). In view of toxicities of L-asparaginase, we planned to study the effect of dose and schedule of Escherichia coli-derived L-asparaginase on early MRD by phasing the same total dose, once a week over 8 weeks. Methods: This prospective, observational study enrolled 45 children and young adults ≤40 years. Modified BFM 95 protocol was followed. Weekly 5000 IU/m2 L-asparaginase was given intravenously, and MRD was analyzed at the end of 4 weeks (MRD1) and at 8 weeks (MRD2), using multicolor flow cytometry. MRD positive was defined as residual blasts ≥0.01%. Results: Thirty-one patients were eligible for final analysis. Nine could receive scheduled eight doses of L-asparaginase and 22 patients received less than eight doses. We analyzed age, gender, diagnosis, prednisone response, cytogenetics, central nervous system status, BFM risk group, MRD2, and relapse. L-asparaginase dose association was not statistically significant with respect to MRD2 (P = 0.237). There were no cases of pancreatitis, hypersensitivity, bleeding, or thrombosis. Reasons for patients receiving less than the scheduled eight doses were low serum fibrinogen levels and liver dysfunction. This study revealed 8 MRD1-negative and 13 MRD2-negative patients. Conclusion: L-asparaginase dose intensity does not affect early MRD. Phasing L-asparaginase over 8 weeks could lead to the achievement of more MRD2-negative status and thereby improve long-term outcome. This strategy may also reduce the incidence of adverse drug events.

Analysis of apoptotic, platelet-derived, endothelial-derived, and tissue factor-positive microparticles of children with acute lymphoblastic leukemia during induction therapy.

Thromboembolism is one of the most common complications during induction therapy of pediatric acute lymphoblastic leukemia (ALL). Procoagulant microparticles in the circulation may cause thromboembolic events. The aim of our study was to determine the levels of apoptotic, platelet-derived, endothelial-derived, and tissue factor-positive microparticles of children with ALL at diagnosis and during induction therapy. Sixteen precursor B-cell ALL cases and 30 healthy children between 1 and 18 years of age were included. Microparticle levels were analyzed from peripheral blood samples at initial diagnosis, on days 12 and 13 (before and after the first L-asparaginase administration), and on day 33 of ALL-BFM 2000 treatment protocol. Microparticle levels were analyzed by using flow cytometry. At initial diagnosis, platelet, endothelial-derived, and tissue factor-positive microparticle levels were significantly high in children with ALL. They increased significantly after prednisone and L-asparaginase administration. Apoptotic microparticle levels were not elevated at diagnosis, but remained high during all induction therapy period. None of the patients had evidence of thromboembolism during induction therapy. Our study demonstrated that children with ALL have increased levels of apoptotic, platelet-derived, endothelial-derived, and tissue factor-positive microprticles during induction therapy. Further studies are needed in larger groups of patients in order to evaluate the risk of elevated microprticles for development of thromboembolism during induction therapy period in children with ALL.

Biochemical peculiarities of liver injury in patients with acute lymphoblastic leukemia of standard risk

The specific chemotherapy (CT) in patients with acute lymphoblastic leukemia (ALL) is accompanied by a risk of the liver functional state violation. However, there are still many unsolved questions regarding the hepatotoxicity of cytostatic drugs, since hepatic tests’ impairment develops not in all patients.Objective — to determine the nature of changes in biochemical liver tests in patients of standard risk in the dynamics of remission induction chemotherapy.Materials and methods. The examinations involved 22 patients with newly diagnosed ALL, from them 8 (36.4 %) women and 14 (63.6 %) men; mean age was (27.8 ± 14.8) years. Patients complied with criteria of the standard risk group, who achieved clinical and hematological remission on the 28th day of treatment. Patients were examined at baseline before the CT and on the 28th day of treatment, the panel biochemical parameters were determined. The severity of hepatotoxic reactions was evaluated according to the criteria of Common Terminology Criteria for Adverse Events (CTCAE), Version 4.02.Results and discussion. The ALL debut in patients of standard risk in 81.8 % of cases was accompanied by violations of the functional liver state characterized by cytolytic, cholestatic and mixed types and did not exceed the 1st grade of CTCAE.The achievement of clinical-hematologic remission was accompanied by a decrease in the number of patients with liver test abnormalities. Increasing activity of ALT, AST, ALP, GGTP, LDH and the concentration of bilirubin and its fractions in the blood serum on the 28th day of therapy was revealed in 14 (63.8 %) patients. In patients with ALL of standard risk without violations of functional liver tests at baseline, during the CT induction, no increase in the activity of ALT, AST, LF, GGTP, LDH, and serum levels of bilirubin and its fractions was observed. The L-asparaginase administration to the patients with ALL of standard risk in the dynamics of remission induction was accompanied by a decrease in the blood serum levels of total protein in 1.3 times compared to the baseline examination (р &lt; 0.05).Conclusions. The conduction of the remission induction to the ALL patients of the standard risk group was characterized by the lowering the serum total protein level, wich did not depend on the transaminases’ activity and was associated with the L-asparaginase treatment; this should be taken into account when choosing the supportive therapy.

SOX12 promotes colorectal cancer cell proliferation and metastasis by regulating asparagine synthesis

The sex-determining region Y (SRY)-box (SOX) family has a crucial role in carcinogenesis and cancer progression. However, the role of SOX12 and the mechanism by which it is dysregulated in colorectal cancer (CRC) remain unclear. Here we analyzed SOX12 expression patterns in two independent CRC cohorts (cohort I, n = 390; cohort II, n = 363) and found that SOX12 was significantly upregulated in CRC, indicating a poor prognosis in CRC patients. Overexpression of SOX12 promoted CRC cell proliferation and metastasis, whereas downregulation of SOX12 hampered CRC aggressiveness. Mechanistically, SOX12 facilitated asparagine synthesis by transactivating glutaminase (GLS), glutamic oxaloacetic transaminase 2 (GOT2), and asparagine synthetase (ASNS). Downregulation of GLS, GOT2, and ASNS blocked SOX12-mediated CRC cell proliferation and metastasis, whereas ectopic expression of GLS, GOT2, and ASNS attenuated the SOX12 knockdown-induced suppression of CRC progression. In addition, serial deletion, site-directed mutagenesis, luciferase reporter, and chromatin immunoprecipitation (ChIP) assays indicated that hypoxia-inducible factor 1α (HIF-1α) directly binds to the SOX12 promoter and induces SOX12 expression. Administration of l-asparaginase decreased SOX12-mediated tumor growth and metastasis. In human CRC samples, SOX12 expression positively correlated with GLS, GOT2, ASNS, and HIF-1α expression. Based on these results, SOX12 may serve as a prognostic biomarker and l-asparaginase represents a potential novel therapeutic agent for CRC.

Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice

Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule.

Plasma ammonia concentration after L-asparaginase therapy in 27 dogs with high-grade lymphoma or leukemia.

To establish the occurrence of increased plasma ammonia concentration after L-asparaginase (L-asp) administration in dogs with high-grade lymphoma or leukemia; to identify risk factors for the development of hyperammonemia after L-asp administration; and to determine occurrence of adverse events related to hyperammonemia. Prospective case controlled study of sequentially enrolled dogs between May 2011 and March 2012. A university veterinary teaching hospital. Twenty-seven dogs with high-grade lymphoma or leukemia. All dogs received L-asp intramuscularly at a median dose of 400IU/kg. Plasma ammonia concentrations were measured at baseline, 16 hours, and 48 hours after L-asp therapy. Clinicopathological abnormalities were assessed to determine risk factors for the development of hyperammonemia. Adverse events following L-asp were recorded. Median plasma ammonia concentrations at baseline, 16 hours, and 48 hours were 26 μmol/L (44μg/dL), 98 μmol/L (166.9μg/dL), and 67 μmol/L (114μg/dL), respectively. Median plasma ammonia concentrations at 16 and 48 hours after administration were significantly increased compared to baseline. Six dogs had adverse events following L-asp administration. No significant clinical signs were noted that could clearly be attributed to hyperammonemia. No risk factors for developing hyperammonemia were identified; however, there was a positive correlation between the development of hyperammonemia at 16- and 48-hour time points. Subclinical hyperammonemia in dogs with lymphoma or leukemia after L-asp administration appears to be common. No risk factors were identified for the development of hyperammonemia after L-asp treatment, and severe adverse events were rare.

Low Incidence of Osteonecrosis in Childhood Acute Lymphoblastic Leukemia Treated With ALL-97 and ALL-02 Study of Japan Association of Childhood Leukemia Study Group.

Purpose Osteonecrosis (ON) is a serious complication of the treatment of childhood acute lymphoblastic leukemia (ALL); however, data relating to ON in Asian pediatric patients with ALL are scarce. Therefore, we performed a retrospective analysis of cohorts of Japanese patients with ALL to clarify the incidence, clinical characteristics, and risk factors of ON. Patients and Methods The incidence and characteristics of ON were determined in patients with ALL (n = 1,662) enrolled in two studies from the Japan Association of Childhood Leukemia Study (JACLS) group (n = 635 and n = 1,027 patients treated with the ALL-97 and ALL-02 protocols, respectively). Results In total, 24 of 1,662 patients suffered from ON, of which 12 of 635 and 12 of 1,027 patients were treated with the ALL-97 and the ALL-02 protocol, respectively. Of the 24 patients, 23 were older than 10 years. In multivariate analysis, age (≥ 10 years) was the sole significant risk factor for ON ( P < .001). Separate evaluation of patients ≥ 10 years of age indicated a 5-year cumulative incidence of ON of 7.2% (95% CI, 4.0% to 12.6%) and 5.9% (95% CI, 3.3% to 10.4%) in the ALL-97 and the ALL-02 protocol, respectively, which was lower than reported previously, despite an administration of dexamethasone (DEX) similar to that in comparable studies; however, concomitant administration of DEX and l-asparaginase was reduced in the JACLS protocols. Conclusion We identified a low frequency of ON in the JACLS ALL-97 and ALL-02 studies. Although the sole risk factor for ON was age (≥ 10 years), even among high-risk patients, ON incidence was significantly lower than that reported in previous studies. These results suggest that, not only the total amount of DEX, but also how DEX and l-asparaginase are administered, which affects the clearance of DEX, may be associated with ON incidence in patients with ALL.

Shift to Anti-Fibrinolysis on the Administration of L-Asparaginase (L-Asp) during Induction Therapy for Pediatric Acute Lymphoblastic Leukemia (ALL)

Introduction: Thromboembolism is a serious complication associated with ALL. The use of central venous catheter and treatment protocols involving corticosteroids and L-Asp is assumed as important thrombogenic factors at the induction phase. In particular, L-Asp has profound effects on hepatic synthesis of pro-, anti-coagulant and fibrinolytic factors. In this study, we hypothesized that change of coagulation and fibrinolytic function contributes to hyper-coagulation condition during the induction phase with L-Asp. In order to clarify this, we evaluated the dynamic change in coagulation and fibrinolysis by simultaneous measurement of both thrombin and plasmin generation assay (T/P-GA). Patients: Twenty-seven pediatric patients with newly diagnosed ALL were enrolled from Aug. 2014 to Oct. 2015 at 3 hospitals in Japan. All cases had no thrombotic predisposition. Eighteen cases (66.7%) (BCP-ALL; n=17, T-ALL; n=1) received Berlin-Frankfürt-Münster (BFM)-95 oriented induction therapy included prednisolone (and dexamethasone for T-ALL), vincristine, daunorubicin, and E.coli L-Asp (a total of 8 doses of 5,000 U/m2). The others (BCP-ALL; n=8, T-ALL; n=1) received Japan Association of childhood Leukemia Study (JACLS) ALL02 oriented induction therapy included prednisolone, dexamethasone, vincristine, daunorubicin, cyclophosphamide and E.coli L-Asp (a total of 6 doses of 6,000 U/m2). Methods: The individual hemostatic parameters were monitored by fibrinogen (Fbg), FDP, AT, TAT and PIC. Additionally, the global functions of coagulation and fibrinolysis were evaluated using T/P-GA established by our group [Matsumoto et al. TH 2013]. This assay was initiated by the addition of a mixture of optimized concentrations of tissue factor and tissue-type plasminogen activator. Thrombin and plasmin generation were monitored simultaneously using individual fluorescent substrates in separate microtiter wells. Standard curves were set using purified alpha-thrombin and plasmin. Patients' plasmas were collected at the following points, T0; pre-phase of L-Asp, T1; intermittent phase of L-Asp, T2; post-phase of L-Asp, and T3; post-induction phase. Endogenous potentials of thrombin generation (T-EP) for coagulant activity and plasmin peak levels (P-Peak) of plasmin generation for fibrinolytic activity were selected as parameters for evaluation in this study. A ratio of T-EP and P-Peak of patients' plasmas to those of control normal plasma were calculated. Results: All cases obtained first remission, and none of them developed coagulopathy. Six cases received FFP transfusion for low Fbg level, whilst 21 cases received AT supplement for low AT level. Fbg showed a median of 170, 99.0, 99.0 and 328 mg/dl at T0, T1, T2 and T3, respectively, whilst the other individual parameters showed relatively unchanged. T-EP revealed a median of 1,126, 1,059, 1,175, 1,343 and 1,132 nM, whilst P-Peak showed a median of 6.67, 4.54, 4.12, 5.50 and 5.77 nM for T0, T1, T2, T3 and control plasma, respectively, indicating the elevated T-EP ratios and reduced P-Peak ratios (Fig. 1). The most significant difference in both ratios demonstrated a median of 1.5-fold (range, 1.0 to 2.6) at T2, consistent with the lowest Fbg levels. The FFP transfusion group showed significantly lower T-EP ratios than non-transfusion group at T1 (a median of 0.87 vs. 1.01, P=0.041) and T2 (a median of 0.96 vs. 1.07, P=0.009), whilst P-Peak ratios revealed no significant changes. The AT supplement group showed no significant changes of both ratios. Conclusion: The results from decreased Fbg and unchanged FDP might reveal the hepatic synthesis disorder of Fbg, whilst the results from T/P-GA showed that their hemostatic dynamics appear likely to be thrombotic tendency, since their coagulation state was hyper-coagulation and anti-fibrinolysis at post-phase of L-Asp. These results suggest that the impaired balance of coagulation and fibrinolysis due to L-Asp therapy might play an important role of a thrombotic complication at induction phase. On the other hand both conventional FFP transfusion and AT supplement therapy might not dramatically repair this unbalance state. A further research would be required to examine the role of coagulant and fibrinolytic function using T/P-GA in the pathogenesis of coagulopathy associated with L-Asp therapy in order to establish the optimal supportive therapy. [Display omitted] DisclosuresNogami:F. Hoffmann-La Roche Ltd.: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Sysmex Corporation: Patents & Royalties, Research Funding; Chugai Pharmaceutical Co., Ltd.: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties, Research Funding. Matsumoto:Sysmex Corporation: Patents & Royalties, Research Funding; Chugai Pharmaceutical Co., Ltd.: Patents & Royalties, Research Funding. Shima:Chugai Pharmaceutical Co., Ltd.: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Patents & Royalties, Research Funding; F. Hoffmann-La Roche Ltd.: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Sysmex Corporation: Patents & Royalties, Research Funding.

Coagulation abnormality as a complication of L-asparaginase therapy in childhood lymphoblastic leukemia

Background Bleeding, one of the most common symptoms ofacute leukemia in untreated patients, is mostly due to thrombocy-topenia as a result of myeloinvasion by leukemic cells. Neverthe-less, a further contributory factor for the additional hemorrhagiccomplication during intensive chemotherapy is the myelosuppressiveeffect of most active drugs. L-asparaginase, one of the cytostaticsused during remission induction therapy for childhood of acutelymphoblastic leukemia (ALL), is widely reported to impair the he-mostatic system.Objective To determine the influence of shorter courses of L-as-paraginase (L-Ase) on some of the hemostatic parameters in thetreatment of childhood ALL.Methods A prospective analytical study was carried out in theDepartment of Child Health, Cipto Mangunkusumo Hospital Jakartafrom July 1, 1999 to June 30, 2001 on newly diagnosed ALL pa-tients with normal liver function tests treated according to our na-tional ALL protocol which one of its composition contained 6 in-stead of 9 injections of L-asparaginase.Results All of 30 children with ALL included in the study, experi-enced prolongation of prothrombin time (PT), activated partialthromboplastin time (aPTT), and decreased fibrinogen concentra-tion, markedly during the administration of L-asparaginase. How-ever, none of the patients had additional hemorrhage or evidenceof disseminated intravascular coagulation (DIC).Conclusion The use of shorter courses of L-asparaginase, 6 in-jections, in the remission induction chemotherapy of childhood ALLin our department may reduce the blood clotting factors withoutfurther hemorrhage complication or evidence of DIC